Background: An important aspect of Quality Assurance in Anatomic Pathology is Frozen Section (FS) discrepancy analysis. The current study was undertaken to analyze the subspecialty FS discrepancy rates in a large volume practice and compare the rates between FSs interpreted with (cosigned) and without subspecialty (non-cosigned) expertise/input.Design: A total of 8,726 FSs from June 2011-May 2012 were analyzed according to Association of Directors of Anatomic and Surgical Pathology guidelines (ADASP) criteria. The reasons for discrepancy were categorized into sampling and interpretation errors.Results: Gross diagnosis was performed on 17 (0.2%) and deferred on 100 (1.2%) FSs. Of the remaining 8,609 FSs, there were 107 (1.24%) discordant cases with 29 major (0.34%) and 78 (0.9%) minor discrepancies (See Table 1).

Analysis

Subspeciality (Total FSs=8609)

Discrepancy Major

Discrepancy Minor (%)

Major Interpretation Discrepancies (%)

Major Sampling Discrepancies (%)

Cosigned FSs (n=517)

Major Cosigned Discrepancies

Major Non-cosigned Discrepancies

ENT (2686)

16 (0.6%)

27 (1%)

3 (0.1%)

13 (0.5%)

166 (6.2%)

1 (0.6%) - Sampling

15 (0.6%) [3-Interpretation, 12-Sampling]

Pulmonary (1154)

0

1 (0.1%)

0

0

51 (4.4%)

0

0

Orthopedic (927)

0

3(0.3%)

0

0

36 (3.9%)

0

0

Genitourinary (820)

2 (0.2%)

8 (0.9%)

0

2 (0.2%)

49 (5.9%)

0

2 (0.3%) - Sampling

Gynecology (642)

1 (0.2%)

5 (0.8%)

1 (0.2%)

0

54 (8.4%)

0

1 (0.2%) - Interpretation

Breast (635)

7 (1.1%)

15 (2.3%)

0

7 (1.1%)

42 (6.6%)

0

7 (1.2%) - Sampling

Neuropathology (580)

0

4 (0.7%)

0

0

7 (1.2%)

0

0

Hepatobiliary (421)

2 (0.5%)

7 (1.7%)

2 (0.5%)

0

38 (9%)

1 (2.6%) - Interpretation

1 (0.3%) - Interpretation

Gastrointestinal (341)

0

3 (0.9%)

0

0

31 (9%)

0

0

Dermatopathology (136)

1 (0.7%)

4 (2.0%)

0

1 (0.7%)

12 (8.8%)

1 (8.3%) - Sampling

0

Hematopathology (116)

0

0

0

0

5 (4.3%)

0

0

Soft tissue (110)

0

1 (0.9%)

0

0

1 (0.9%)

0

0

Eye (33)

0

0

0

0

0

0

0

Cardiac (18)

0

0

0

0

0

0

0

A total of 517 (6%) FSs were cosigned with the corresponding subspecialty pathologist. In specialities with same or slightly higher discrepancy rates in the non-cosigned group compared to the cosigned group, there were 4 interpretation errors (3- ENT, 1-gynecology). Hepatobiliary pathology was the only speciality where the discrepancy rate was higher in the cosigned group due to an interpretation error (n=1).Conclusions: The discrepancy rates in subspecialty practice setting are well within acceptable standards. Most discrepancies are due to sampling errors. As interpretation errors without subspecialty expertise are rare, FS practice may not require a dedicated subspecialized service.Category: Quality Assurance